The design of the Spider was based on that of the earlier Targa. However, the front, back, and sides were all slightly restyled to accommodate for a convertible. Also, a laterally-curved line was present on the body as opposed to the straight line on the Targa.
During the Spider's production, it was fitted with three different engines. In 1983 and 1984, cars were mounted with a 1,588cc four-cylinder Volkswagen 6000 motor, which could produce 88 hp of power at 5,800 rpm and 13.3 kgf·m of torque at 3,000 rpm. The 1,781cc water-cooled Volkswagen 1800 was used from 1984 to 1985, and was capable of delivering 96 hp of power at 5,200 rpm and generating 15.6 kgf·m of torque at 3,400 rpm. A four-cylinder Volkswagen 800 AP of the same displacement was utilized from 1986 onward, and was able to generate 92 hp of power at 5,000 rpm and 14.6 kgf·m of torque at 2,800 rpm. With the original motor, the Spider could reach speeds up to 165 km/h and accelerate to 100 km/h in as little as 14 seconds. Cars mounted with the 800 AP could reach up to 175 km/h and accelerate from 0 to 100 in 13 seconds. Both engines were accompanied by a five-speed gearbox. Braking was done with discs in the front and drums in the rear. For suspension, the front used independent McPherson struts with a stabilizer, whereas the back utilized an independent rigid axle. Standard features included an electrically-openable trunk, an electric defogger, retractable steering, electric windows, and heating and air conditioning. Optional with the Spider was an on-board computer with a voice synthesizer, which would eventually come standard in later Miura models. The car measured 4.27 m in length and 1.59 m in width, and weighed approximately 895 kg. It rode on a wheelbase of 2.42 m.